Simple AC Static Single Pole Double Throw Switch Circuit Diagram

This is a Simple AC Static Single Pole Double Throw Switch Circuit Diagram. SPDT is a a simple type of changeover electrical switch. An SPDT solid state relay is shown. When voltage is applied Ql will turn on, activating load 1, because the full line voltage appears across Q2, supplying gate current through Rl. When SI is closed. Q2 turns on removing the gate drive from Ql and activating load 2. AC Static Single Pole Double Throw Switch Circuit Diagram